1. Field of the Invention
The present invention relates to a recyclable formwork whose working condition can be easily known. The recyclable formwork is represented by a plastic formwork. The recyclable formwork, however, may be not only the plastic formwork but also a metal formwork, especially a formwork of aluminium, iron, or steel, as long as characteristics thereof, such as a weight, a price, or the like are suitable.
2. Description of the Related Art
Countermeasures against greenhouse gas represented by carbon dioxide are important subjects in which human beings should immediately aim to solve. Carbon dioxide reduction should be carried out strongly without damaging an economy. The inventors will discuss a new proposition in a field of formworks used for curing concrete.
Until now, formworks are mainly concrete panels made of tropical wood.
Instead of the concrete panels, plastic formworks are developed and used. Some types of the plastic formworks can be perfectly recycled and are regarded as next-generafion formworks.
However, there are the following probletns with respect to the plastic formworks. First, a unit price of the plastic formworks is about five times of that of concrete panels. Secondly, initial investment for the plastic formworks is extensive. Furthermore, the investment cannot be amortized in one construction field.
As for costs considering a number of repetitive use times the first number of repetitive use times of the concrete panels are normally about five, and the second number of repetitive use times of the plastic formworks is about fifty, that is, ten times of the first number. As for costs per one time use, which is obtained by dividing the unit prices by the numbers of repetitive use times, the concrete panels is almost the double of the plastic formworks. The plastic formworks are superior to the concrete panels with respect to not only environmental load but also the cost per one time use.
However, since there is no means for effectively managing a long used time of the plastic formworks, the plastic formworks have not been practically and widely used yet.
The formworks are brought to a construction field to be built there. Next, concrete is cast between the built formworks for curing, the concrete is hardened and solidified, and then the formworks are removed. However, curing time remarkably differs according to portions of a structure to be built, such as a wall, a beam, and a floor.
There is no technical means for managing the formworks taking the differences of curing time caused by the portions where the formworks are used into consideration. Actually, a construction supervisor of the construction field and the men use the formworks on their hunches.
In short, it is impossible to solve the above problem with conventional plastic formworks and it is necessary to add a new function to the conventional plastic formworks. Furthermore, consideration must be done such that the added new function does not spoil the other functions of the plastic formworks. Technique that satisfies such requirement has not been known yet.
A sensing function is one of the functions to be added. With respect to each recyclable formwork, it is required to manage the remainder of use times until next recycling, concrete temperature determining quality of concrete-curing, and so on by managing the used time. The present invention particularly relates to managing concrete temperature among these subjects.                [Document 1] Japanese patent application Laid-open on No. H07-26717        [Document 2] Japanese patent application Laid-open on No. H07-229297        